Chiral compounds are employed as structural units for the synthesis of pharmaceutical active compounds. It is desirable that these compounds are stable on storage and moreover can be prepared and purified simply in order to ensure constant quality, to avoid frequent checks of the materials for keeping a record of the product quality, to avoid the necessity for cold-storage depots and/or refrigerated transport, to guarantee easy filling in production plants and/or to guarantee the simple cleaning of used containers.
Viscous oils can often only be poured into another container or weighed exactly with difficulty. Moreover, the purification of oils or viscous liquids can in many cases only be carried out with considerable outlay in terms of apparatus. In addition, oils can exhibit nonoptimal behaviour on dissolving in solvents, for which reason the mixing of liquids having different densities and viscosities must be monitored with particular care.
(2R)-2-Bromo-3-phenylpropionic acid is a viscous oil which has several of the disadvantageous properties listed above. Use of (2R)-2-bromo-3-phenylpropionic acid on the industrial scale is therefore associated with difficulties and additional costs.